Method of manufacturing headers for water-tube boilers and the like.



J. PIELDING. METHOD OF MANUFACTURING HEADERS FOR WATER TUBE BOILERS ANDTHE LIKE.

APPLICATION FILED JULY 6, 1909.

Patented May 30, 1911.

Z SHEETS-SHEET 1.

THE NORRIS PETERS 60 WA J. PIELDING. METHOD OF MANUFACTURING HEADERS FORWATER TUBE BOILERS AND THE LIKE.

APPLICATION FILED JULY 6, 1909.

Patented May 30, 1911.

2 SHEETS-SHEET 2.

1N5 NORRIS PETERS cm. wAsmzvnwn, 0 cv JOHN FIELDING, OF GLOUCESTER,ENGLAND.

METHOD OF MANUFACTURING HEADERS FOR WATER-TUBE BOILERS AND THE LIKE.

To all whom it may concern:

Be it known that I, JoI-IN FIELDING, a subject of the King of GreatBritain, residing at Atlas Works, Gloucester, in the county ofGloucester, England, engineer, have invented a certain new and usefulImproved Method of Manufacturing Headers for VVater-Tube Boilers or theLike, of which the following is a specification.

This invention refers to serpentine headers for tubulous boilers or thelike and consists in an improved method of making such headers.

Tubular blanks have been given an irregular outline by either inclosingthem in suitable dies and subjecting them internally to fluid pressureto force the blank out against thewalls of the incasing dies, or byinserting in the blank a collapsible sectional mandrel havingdepressions on its sides corresponding to the required form and heldtogether and in place by a central core, then placing the blank betweenupper and lower dies with plain faces and side dies with depressions ontheir acting faces corresponding to the projecting surfaces of theserpentine faces of the mandrel, and forcing the dies together toproduce the desired form; but in both these methods the boring orpunching and flanging of the tube and hand holes have constitutedseparate operations. It has been proposed also to insert metal plates ina punching and forming machine and to move the plates forwardly or in anoutward direction against dies carried by the machine, whereby holes arepunched in the plates, backwardly or inwardly directed flanges impartedto the margin of each hole and the plates themselves convexed in theoutward direction, but these plates thus punched and formed would haveto undergo a separate and subsequent operation in order to form theminto serpentine headers for tubular boilers.

According to the present invention by means of internal and externalpunches and dies of suitable shape and cooperating together, theoperations necessary to impart to the tubular blank which is toconstitute the header a sinuous or serpentine shape, also to punch holesin one face of the blank and to punch and outwardly flange a series ofholes in another face, are all carried out successively butsubstantially simultaneously and with one heating and one working of thetube blank whereby a considerable saving of labor and time is effected.

Specification of Letters Patent.

Application filed July 6, 1909.

Patented May 30, 1911.

Serial No. 506,071.

The external dies consist of a pair of plane surface dies between whichthe tube is firmly held on two opposite faces; there are also a pair ofcorrugated pressing dies, one or both of which are operated by suitablemeans, such as hydraulic rams, to give the serpentine form to the otherfaces of the tube. The first pair of dies are fitted with punches anddies placed at suitable centers for the purpose of punching and flangingthe tube holes as will be hereinafter described.

The internal dies consist of as many pairs of convex and concave dies asthere are intended to be tubes in the header; these are speciallyconstructed so that they may be easily removed from the finished tube.These convex and concave dies are held in their relative positions inregard to each other by a central punch which forms a sort of key tothem, the convex die of one pair faces one side of the tube, while thatof the adjacent pair faces in the opposite direction, and so on, theconvex dies are D-shaped and fit around rather more than half thecircumference of the central punch, so that when put into the straighttube their sides butt against each other and thereby maintain thecorrect pitch from center to center of the punches and dies, thesecenters being arranged to agree with those of the corrugations andpunches in the external dies.

The internal dies are held in their proper positions by dies which enterthe ends of the header, and are urged inward preferably by means ofhydraulic rams. One of these end dies and hydraulic rams are used topush the internal dies into the tube from a channel or guide in whichthey are placed in readiness. lVhen the corrugated external dies arepressed upon the tube, the internal dies prevent the collapsing of thetube, but each pair follows the movement which takes place as the tubeis pressed into serpentine form. l/Vhen thus pressed, the centers of theinternal punches are brought into line with the punches on the externaldies already referred to.

There are punches in one of the plane surface dies only, the oppositeplane surface die being bored large enough to form the mold or die intowhich the adjacent side of the tube is to be flanged after punching, andwithin this flanging mold is fitted a sliding punching die having acentral hole corresponding to but somewhat larger than a projectionwhich is formed upon the central internal punch. This sliding die isheld level with the surface of the external die during the punchingoperation. In the other end of the central internal punch is bored arecess somewhat larger in diameter than the punch in the correspondingexternal plane die and of a depth about equal to the thickness of theadjacent side of the tube.

lVhen the punches in the external die are forced forward the side of thetube nearest is punched, the metal being forced into the recess in theinternal punch, the recess being thus filled up; the continued advanceof the external punch forces the internal punch forward punching theother side of the tube. Both sides being thus punched the sliding dieabove referred to is released or withdrawn and the central punch isdriven out of the tube thus forming the flange around the hole lastpunched. The punching and corrugating dies are then drawn back and thetube taken out and the convex and concave dies can now be removed; thesedies are made each in two pieces to allow of this being done.

The improved method of manufacture will be described with reference toone form of apparatus suitable for carrying out the invention, whichapparatus is illustrated in the drawings accompanying this specification, in which Figures 1 and 2 are plans of the apparatus in twopositions; Fig. 3 is a sectional eleva tion; and Figs. 4 and 5 aresectional views of the apparatus drawn to a larger scale.

In Fig. 1 the plain tube which it is intended to form into a corrugatedand flanged header and which is preferably of rectangular section, isshown at 1 heated ready for being operated upon; 2 is an open channel orbox in which are contained the internal dies 3, 4, punches 5 which arepressed together by end dies 6, 7, and these latter dies are operated byhydraulic rams 8 and 9. lVater being exhausted from cylinder 8 of ram 8,the dies are pushed by ram 9 into the tube 1, and as soon as thecrosshead 10 on ram 9 comes against the rear end of the tube 1, thelatter is pushed forward along with the internal dies into the space 11until the centers of the punches 5 are coincident with the lines 11which intersect the axes of two holes 21 (see Fig. 3) in the bot tomplate 20 of the external mold or die,

which holes act as dies for flanging the lips of the hand or other holesto be formed on the header. l Vhen the tube is in this position it issubjected to lateral pressure from the corrugating dies 12 operated bysuitable gear such as the toggle links 18 and hydraulic rams 14.Preferably these rams are connected by some convenient gear to insuretheir simultaneous One arrangement for connecting the cams is shown inFigs. 1 and 2. The toggle links are connected together and with the ram14 by linkage 13 13 and links 13 are connected to ram 14 by linkage 1313". Links 13 are also connected to a ram 14 by a link 13*, and links 13are connected by means of link 13 and pivoted beam lever 14 to ram 14.Rams 14 and 14 when operated actuate the links 13 and 13 to causecorrugating dies 12 to move toward one another, and ram 14 actuates thelinks to cause a return motion of the dies.

Fig. 3 shows in sectional elevation the same parts and also thearrangement of the punching and fianging dies. In this view the partsalready described are indicated by the same numbers as in the previousviews other parts being a crosshead or platen 15 carrying the punches 16and operated by a suitable hydraulic ram 17. 18, 18 are a pair ofhydraulic rams working on the plane surface die or plate 19 which formsthe top of the external mold or die and acts also as a guide for thepunches 16. This plate 19 can be lifted high enough to allow of the easyremoval of the finished header. 20 is a plate which forms the bottom ofthe external mold and has holes 21 bored in it to form the mold forfianging the lips of the holes to be formed on the header. These holesare shown in the drawing, Fig. 3, as filled up by members 22 carried orformed upon a moving or sliding table 23 operated by rams 24. Themembers 22 serve as dies for the holes to be punched in one of the sidesof the tube. The operation of punching and flanging is described withreference to Figs. 4 and 5 in which the different parts are numbered asbefore. These figures are transverse sections through one pair of theholes 21.

Fig. 4 shows the punching operation; Fig. 5 the method of flanging thelip. The internal punching die 5 is operated by the punch 16 and ram 15.The sliding punching die 22 has a central hole 22 corresponding to butsomewhat larger than a projection 5 formed upon punch die 5, and duringthe punching operation it is raised by rams 24 so that it enters hole 21and is held there level with the top of internal die 20, Fig. 4. In theupper end of the die 5 is bored a recess 5 somewhat larger in diameterthan the punch 16 and of a depth about equal to the thickness of thetube in that part.

hen punch 16 is pressed by platen 15 and ram 17 it first punches oneplane face of the tube and the punched disk is forced out and fills uprecess 5 As punch 16 advances farther the internal punch 5 is forcedforward to punch the other plane face of the tube. The sliding punch dieis then withdrawn, and the internal punch is drawn farther out of thetube and thus forms a flange around the hole last punched. The disk 23last punched out either falls out of or can be removed from the table23. The external punching and corrugating dies are now drawn back, thetube removed from space 11 and the convex and concave internal dieswithdrawn from the tube by any suitable means.

Having thus described the nature of my said invention and the best meansI know of carrying the same into practical eifect, I claim 1. A methodof forming an integral tubular blank into a corrugated or serpentineheader for a tubulous boiler and holeing it in one operation, whichconsists in pressing the blank, while the latter is stationary, in twoopposing directions to impart a serpentine form thereto, punching holesin the blank, said holes having axes transverse to the said direction,and fianging outwardly the margins of the holes.

2. A method of forming an integral tubular blank into a corrugated orserpentine header for a tubulous boiler and holeing it in one operation,which consists in first pressing the blank, while the latter isstationary, in two opposing directions to impart a serpentine formthereto, then punching from without the blank a series of holes therein,having axes transverse to the said directions, then punching from withinthe blank a second series of holes, and finally fianging outwardly themargins of the second series of holes.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

JOHN FIELDING. [1 8.]

WVitnesses:

CECIL B. GREENHILL, P. LOISU.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

